VPP-305: Documentation for vnet/vnet/unix

Change-Id: I3f1a225033ecebe0cedfc3466b552176461b76ab
Signed-off-by: Keith Burns (alagalah) <alagalah@gmail.com>

8 files changed, 647 insertions, 158 deletions

diff --git a/vnet/vnet/unix/gdb_funcs.c b/vnet/vnet/unix/gdb_funcs.c
index 9a2e4599a2b..cfb4b247800 100644
--- a/vnet/vnet/unix/gdb_funcs.c
+++ b/vnet/vnet/unix/gdb_funcs.c
@@ -12,33 +12,73 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+/**
+ * @file
+ * @brief Host utility functions
+ */
 #include <vppinfra/format.h>
 #include <vlib/vlib.h>
 
 #include <vlib/threads.h>
 
-/* Functions to call from gdb */
 
+
+/**
+ * @brief GDB callable function: vl - Return vector length of vector
+ *
+ * @param *p - void - address of vector
+ *
+ * @return length - u32
+ *
+ */
 u32 vl(void *p)
 {
   return vec_len (p);
 }
 
+/**
+ * @brief GDB callable function: pe - call pool_elts - number of elements in a pool
+ *
+ * @param *v - void - address of pool
+ *
+ * @return number - uword
+ *
+ */
 uword pe (void *v)
 {
   return (pool_elts(v));
 }
 
+/**
+ * @brief GDB callable function: pifi - call pool_is_free_index - is passed index free?
+ *
+ * @param *p - void - address of pool
+ * @param *index - u32
+ *
+ * @return 0|1 - int
+ *
+ */
 int pifi (void *p, u32 index)
 {
   return pool_is_free_index (p, index);
 }
 
+/**
+ * @brief GDB callable function: debug_hex_bytes - return formatted hex string
+ *
+ * @param *s - u8
+ * @param n - u32 - number of bytes to format
+ *
+ */
 void debug_hex_bytes (u8 *s, u32 n)
 {
   fformat (stderr, "%U\n", format_hex_bytes, s, n);
 }
 
+/**
+ * @brief GDB callable function: vlib_dump_frame_ownership
+ *
+ */
 void vlib_dump_frame_ownership (void)
 {
   vlib_main_t * vm = vlib_get_main();
@@ -47,7 +87,7 @@ void vlib_dump_frame_ownership (void)
   vlib_next_frame_t * nf;
   u32 first_nf_index;
   u32 index;
-    
+
   vec_foreach(this_node_runtime, nm->nodes_by_type[VLIB_NODE_TYPE_INTERNAL])
     {
       first_nf_index = this_node_runtime->next_frame_index;
@@ -74,11 +114,18 @@ void vlib_dump_frame_ownership (void)
     }
 }
 
+/**
+ * @brief GDB callable function: vlib_runtime_index_to_node_name
+ *
+ * Takes node index and will return the node name.
+ *
+ * @param index - u32
+ */
 void vlib_runtime_index_to_node_name (u32 index)
 {
   vlib_main_t * vm = vlib_get_main();
   vlib_node_main_t * nm = &vm->node_main;
-    
+
   if (index > vec_len (nm->nodes))
     {
       fformat(stderr, "%d out of range, max %d\n", vec_len(nm->nodes));
@@ -89,6 +136,13 @@ void vlib_runtime_index_to_node_name (u32 index)
 }
 
 
+/**
+ * @brief GDB callable function: show_gdb_command_fn - show gdb
+ *
+ * Shows list of functions for VPP available in GDB
+ *
+ * @return error - clib_error_t
+ */
 static clib_error_t *
 show_gdb_command_fn (vlib_main_t * vm,
                      unformat_input_t * input,
diff --git a/vnet/vnet/unix/pcap.c b/vnet/vnet/unix/pcap.c
index 1c5f033ea1f..5c8a14bd29c 100644
--- a/vnet/vnet/unix/pcap.c
+++ b/vnet/vnet/unix/pcap.c
@@ -40,24 +40,33 @@
 #include <vnet/unix/pcap.h>
 #include <sys/fcntl.h>
 
-/* Usage
-
-#include <vnet/unix/pcap.h>
-
-static pcap_main_t pcap = {
-  .file_name = "/tmp/ip4",
-  .n_packets_to_capture = 2,
-  .packet_type = PCAP_PACKET_TYPE_ip,
-};
-
-To add a buffer:
-
-  pcap_add_buffer (&pcap, vm, pi0, 128);
-
-file will be written after n_packets_to_capture or call to pcap_write (&pcap).
-
+/**
+ * @file
+ * @brief PCAP function.
+ *  Usage
+ *
+ * #include <vnet/unix/pcap.h>
+ *
+ * static pcap_main_t pcap = {
+ *  .file_name = "/tmp/ip4",
+ *  .n_packets_to_capture = 2,
+ *  .packet_type = PCAP_PACKET_TYPE_ip,
+ * };
+ *
+ * To add a buffer:
+ *
+ *  pcap_add_buffer (&pcap, vm, pi0, 128);
+ *
+ * File will be written after n_packets_to_capture or call to pcap_write (&pcap).
+ *
 */
 
+/**
+ * @brief Close PCAP file
+ *
+ * @return rc - clib_error_t
+ *
+ */
 clib_error_t *
 pcap_close (pcap_main_t * pm)
 {
@@ -67,6 +76,12 @@ pcap_close (pcap_main_t * pm)
   return 0;
 }
 
+/**
+ * @brief Write PCAP file
+ *
+ * @return rc - clib_error_t
+ *
+ */
 clib_error_t *
 pcap_write (pcap_main_t * pm)
 {
@@ -143,6 +158,12 @@ pcap_write (pcap_main_t * pm)
   return error;
 }
 
+/**
+ * @brief Read PCAP file
+ *
+ * @return rc - clib_error_t
+ *
+ */
 clib_error_t * pcap_read (pcap_main_t * pm)
 {
   clib_error_t * error = 0;
@@ -197,7 +218,7 @@ clib_error_t * pcap_read (pcap_main_t * pm)
 	  error = clib_error_return (0, "short read `%s'", pm->file_name);
 	  goto done;
 	}
-	
+
       if (vec_len (pm->packets_read) == 0)
 	pm->min_packet_bytes = pm->max_packet_bytes = ph.n_bytes_in_packet;
       else
@@ -205,7 +226,7 @@ clib_error_t * pcap_read (pcap_main_t * pm)
 	  pm->min_packet_bytes = clib_min (pm->min_packet_bytes, ph.n_bytes_in_packet);
 	  pm->max_packet_bytes = clib_max (pm->max_packet_bytes, ph.n_bytes_in_packet);
 	}
-	
+
       vec_add1 (pm->packets_read, data);
     }
 
@@ -213,5 +234,5 @@ clib_error_t * pcap_read (pcap_main_t * pm)
   if (fd >= 0)
     close (fd);
   return error;
-  
+
 }
diff --git a/vnet/vnet/unix/pcap.h b/vnet/vnet/unix/pcap.h
index 89eca031185..6aaf32bef7e 100644
--- a/vnet/vnet/unix/pcap.h
+++ b/vnet/vnet/unix/pcap.h
@@ -36,13 +36,25 @@
  *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
-
+/**
+ * @file
+ * @brief PCAP utility definitions
+ */
 #ifndef included_vnet_pcap_h
 #define included_vnet_pcap_h
 
 #include <vlib/vlib.h>
 
-#define foreach_vnet_pcap_packet_type		\
+/**
+ * @brief Packet types supported by PCAP
+ *
+ * null 0
+ * ethernet 1
+ * ppp 9
+ * ip 12
+ * hdlc 104
+ */
+#define foreach_vnet_pcap_packet_type           \
   _ (null, 0)					\
   _ (ethernet, 1)				\
   _ (ppp, 9)					\
@@ -56,27 +68,27 @@ typedef enum {
 } pcap_packet_type_t;
 
 #define foreach_pcap_file_header			\
-  /* 0xa1b2c3d4 host byte order.			\
+  /** 0xa1b2c3d4 host byte order.			\
      0xd4c3b2a1 => need to byte swap everything. */	\
   _ (u32, magic)					\
 							\
-  /* Currently major 2 minor 4. */			\
+  /** Currently major 2 minor 4. */			\
   _ (u16, major_version)				\
   _ (u16, minor_version)				\
 							\
-  /* 0 for GMT. */					\
+  /** 0 for GMT. */					\
   _ (u32, time_zone)					\
 							\
-  /* Accuracy of timestamps.  Typically set to 0. */	\
+  /** Accuracy of timestamps.  Typically set to 0. */	\
   _ (u32, sigfigs)					\
 							\
-  /* Size of largest packet in file. */			\
+  /** Size of largest packet in file. */                \
   _ (u32, max_packet_size_in_bytes)			\
 							\
-  /* One of vnet_pcap_packet_type_t. */			\
+  /** One of vnet_pcap_packet_type_t. */                \
   _ (u32, packet_type)
 
-/* File header. */
+/** File header struct */
 typedef struct {
 #define _(t, f) t f;
   foreach_pcap_file_header
@@ -84,58 +96,79 @@ typedef struct {
 } pcap_file_header_t;
 
 #define foreach_pcap_packet_header					\
-  /* Time stamp in seconds and microseconds. */				\
+  /** Time stamp in seconds  */                                         \
   _ (u32, time_in_sec)							\
+  /** Time stamp in microseconds. */                                    \
   _ (u32, time_in_usec)							\
 									\
-  /* Number of bytes stored in file and size of actual packet. */	\
+  /** Number of bytes stored in file. */                                \
   _ (u32, n_packet_bytes_stored_in_file)				\
+  /** Number of bytes in actual packet. */                              \
   _ (u32, n_bytes_in_packet)
 
-/* Packet header. */
+/** Packet header. */
 typedef struct {
 #define _(t, f) t f;
   foreach_pcap_packet_header
 #undef _
 
-  /* Packet data follows. */
+  /** Packet data follows. */
   u8 data[0];
 } pcap_packet_header_t;
 
+/**
+ * @brief PCAP main state data structure
+ */
 typedef struct {
-  /* File name of pcap output. */
+  /** File name of pcap output. */
   char * file_name;
 
-  /* Number of packets to capture. */
+  /** Number of packets to capture. */
   u32 n_packets_to_capture;
 
+  /** Packet type */
   pcap_packet_type_t packet_type;
 
-  /* Number of packets currently captured. */
+  /** Number of packets currently captured. */
   u32 n_packets_captured;
 
+  /** flags */
   u32 flags;
 #define PCAP_MAIN_INIT_DONE (1 << 0)
 
-  /* File descriptor for reading/writing. */
+  /** File descriptor for reading/writing. */
   int file_descriptor;
 
+  /** Bytes written */
   u32 n_pcap_data_written;
 
-  /* Vector of pcap data. */
+  /** Vector of pcap data. */
   u8 * pcap_data;
 
-  /* Packets read from file. */
+  /** Packets read from file. */
   u8 ** packets_read;
 
+  /** Min/Max Packet bytes */
   u32 min_packet_bytes, max_packet_bytes;
 } pcap_main_t;
 
-/* Write out data to output file. */
+/** Write out data to output file. */
 clib_error_t * pcap_write (pcap_main_t * pm);
 
+/** Read data from file. */
 clib_error_t * pcap_read (pcap_main_t * pm);
 
+/**
+ * @brief Add packet
+ *
+ * @param *pm - pcap_main_t
+ * @param time_now - f64
+ * @param n_bytes_in_trace - u32
+ * @param n_bytes_in_packet - u32
+ *
+ * @return Packet Data
+ *
+ */
 static inline void *
 pcap_add_packet (pcap_main_t * pm,
 		 f64 time_now,
@@ -155,6 +188,15 @@ pcap_add_packet (pcap_main_t * pm,
   return h->data;
 }
 
+/**
+ * @brief Add buffer (vlib_buffer_t) to the trace
+ *
+ * @param *pm - pcap_main_t
+ * @param *vm - vlib_main_t
+ * @param buffer_index - u32
+ * @param n_bytes_in_trace - u32
+ *
+ */
 static inline void
 pcap_add_buffer (pcap_main_t * pm,
 		 vlib_main_t * vm, u32 buffer_index,
@@ -179,7 +221,7 @@ pcap_add_buffer (pcap_main_t * pm,
       b = vlib_get_buffer (vm, b->next_buffer);
     }
 
-  /* Flush output vector. */
+  /** Flush output vector. */
   if (vec_len (pm->pcap_data) >= 64*1024
       || pm->n_packets_captured >= pm->n_packets_to_capture)
     pcap_write (pm);
diff --git a/vnet/vnet/unix/pcap2pg.c b/vnet/vnet/unix/pcap2pg.c
index 10b47c976dc..217a61f4cb4 100644
--- a/vnet/vnet/unix/pcap2pg.c
+++ b/vnet/vnet/unix/pcap2pg.c
@@ -14,14 +14,21 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
+/**
+ * @file
+ * @brief Functions to convert PCAP file format to VPP PG (Packet Generator)
+ *
+ */
 #include <vnet/unix/pcap.h>
 #include <vnet/ethernet/packet.h>
 #include <stdio.h>
 
 pcap_main_t pcap_main;
 
-static char * pg_fmt = 
+/**
+ * @brief char * to seed a PG file
+ */
+static char * pg_fmt =
   "packet-generator new {\n"
   "    name s%d\n"
   "    limit 1\n"
@@ -29,16 +36,32 @@ static char * pg_fmt =
   "    node ethernet-input\n";
 
 
+/**
+ * @brief Packet Generator Stream boilerplate
+ *
+ * @param *ofp - FILE
+ * @param i - int
+ * @param *pkt - u8
+ */
 void stream_boilerplate (FILE *ofp, int i, u8 * pkt)
 {
   fformat(ofp, pg_fmt, i, vec_len(pkt), vec_len(pkt));
 }
 
+/**
+ * @brief Conversion of PCAP file to PG file format
+ *
+ * @param *pm - pcap_main_t
+ * @param *ofp - FILE
+ *
+ * @return rc - int
+ *
+ */
 int pcap2pg (pcap_main_t * pm, FILE *ofp)
 {
   int i, j;
   u8 *pkt;
-   
+
   for (i = 0; i < vec_len (pm->packets_read); i++)
     {
       int offset;
@@ -51,13 +74,13 @@ int pcap2pg (pcap_main_t * pm, FILE *ofp)
       stream_boilerplate (ofp, i, pkt);
 
       fformat (ofp, "    data {\n");
-      
+
       ethertype = clib_net_to_host_u16 (h->type);
 
-      /* 
+      /**
        * In vnet terms, packet generator interfaces are not ethernets.
        * They don't have vlan tables.
-       * This dance transforms captured 802.1q VLAN packets into 
+       * This transforms captured 802.1q VLAN packets into
        * regular Ethernet packets.
        */
       if (ethertype == 0x8100 /* 802.1q vlan */)
@@ -69,7 +92,7 @@ int pcap2pg (pcap_main_t * pm, FILE *ofp)
       else
         offset = 14;
 
-      fformat (ofp, 
+      fformat (ofp,
                "          0x%04x: %02x%02x.%02x%02x.%02x%02x"
                " -> %02x%02x.%02x%02x.%02x%02x\n",
                ethertype,
@@ -97,6 +120,10 @@ int pcap2pg (pcap_main_t * pm, FILE *ofp)
   return 0;
 }
 
+/**
+ * @brief pcap2pg.
+ * usage: pcap2pg -i <input-file> [-o <output-file>]
+ */
 int main (int argc, char **argv)
 {
   unformat_input_t input;
diff --git a/vnet/vnet/unix/tapcli.c b/vnet/vnet/unix/tapcli.c
index 7e2ee06330a..608b22098b1 100644
--- a/vnet/vnet/unix/tapcli.c
+++ b/vnet/vnet/unix/tapcli.c
@@ -1,4 +1,4 @@
-/* 
+/*
  *------------------------------------------------------------------
  * tapcli.c - dynamic tap interface hookup
  *
@@ -16,12 +16,16 @@
  * limitations under the License.
  *------------------------------------------------------------------
  */
+/**
+ * @file
+ * @brief  dynamic tap interface hookup
+ */
 
 #include <fcntl.h>		/* for open */
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
-#include <sys/types.h> 
+#include <sys/types.h>
 #include <sys/uio.h>		/* for iovec */
 #include <netinet/in.h>
 
@@ -48,22 +52,39 @@ static vlib_node_registration_t tapcli_rx_node;
 static void tapcli_nopunt_frame (vlib_main_t * vm,
                                  vlib_node_runtime_t * node,
                                  vlib_frame_t * frame);
+/**
+ * @brief Struct for the tapcli interface
+ */
 typedef struct {
   u32 unix_fd;
   u32 unix_file_index;
   u32 provision_fd;
-  u32 sw_if_index;              /* for counters */
+  /** For counters */
+  u32 sw_if_index;
   u32 hw_if_index;
   u32 is_promisc;
   struct ifreq ifr;
   u32 per_interface_next_index;
-  u8 active;                    /* for delete */
+  /** for delete */
+  u8 active;
 } tapcli_interface_t;
 
+/**
+ * @brief Struct for RX trace
+ */
 typedef struct {
   u16 sw_if_index;
 } tapcli_rx_trace_t;
 
+/**
+ * @brief Function to format TAP CLI trace
+ *
+ * @param *s - u8 - formatting string
+ * @param *va - va_list
+ *
+ * @return *s - u8 - formatted string
+ *
+ */
 u8 * format_tapcli_rx_trace (u8 * s, va_list * va)
 {
   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
@@ -75,54 +96,67 @@ u8 * format_tapcli_rx_trace (u8 * s, va_list * va)
   return s;
 }
 
+/**
+ * @brief TAPCLI main state struct
+ */
 typedef struct {
-  /* Vector of iovecs for readv/writev calls. */
+  /** Vector of iovecs for readv/writev calls. */
   struct iovec * iovecs;
 
-  /* Vector of VLIB rx buffers to use.  We allocate them in blocks
+  /** Vector of VLIB rx buffers to use.  We allocate them in blocks
      of VLIB_FRAME_SIZE (256). */
   u32 * rx_buffers;
 
-  /* tap device destination MAC address. Required, or Linux drops pkts */
+  /** tap device destination MAC address. Required, or Linux drops pkts */
   u8 ether_dst_mac[6];
 
-  /* Interface MTU in bytes and # of default sized buffers. */
+  /** Interface MTU in bytes and # of default sized buffers. */
   u32 mtu_bytes, mtu_buffers;
 
-  /* Vector of tap interfaces */
+  /** Vector of tap interfaces */
   tapcli_interface_t * tapcli_interfaces;
 
-  /* Vector of deleted tap interfaces */
+  /** Vector of deleted tap interfaces */
   u32 * tapcli_inactive_interfaces;
 
-  /* Bitmap of tap interfaces with pending reads */
+  /** Bitmap of tap interfaces with pending reads */
   uword * pending_read_bitmap;
 
-  /* Hash table to find tapcli interface given hw_if_index */
+  /** Hash table to find tapcli interface given hw_if_index */
   uword * tapcli_interface_index_by_sw_if_index;
-  
-  /* Hash table to find tapcli interface given unix fd */
+
+  /** Hash table to find tapcli interface given unix fd */
   uword * tapcli_interface_index_by_unix_fd;
 
-  /* renumbering table */
+  /** renumbering table */
   u32 * show_dev_instance_by_real_dev_instance;
 
-  /* 1 => disable CLI */
+  /** 1 => disable CLI */
   int is_disabled;
 
-  /* convenience */
+  /** convenience - vlib_main_t */
   vlib_main_t * vlib_main;
+  /** convenience - vnet_main_t */
   vnet_main_t * vnet_main;
+  /** convenience - unix_main_t */
   unix_main_t * unix_main;
 } tapcli_main_t;
 
 static tapcli_main_t tapcli_main;
 
-/*
- * tapcli_tx
- * Output node, writes the buffers comprising the incoming frame 
+/**
+ * @brief tapcli TX node function
+ * @node tap-cli-tx
+ *
+ * Output node, writes the buffers comprising the incoming frame
  * to the tun/tap device, aka hands them to the Linux kernel stack.
- * 
+ *
+ * @param *vm - vlib_main_t
+ * @param *node - vlib_node_runtime_t
+ * @param *frame - vlib_frame_t
+ *
+ * @return n_packets - uword
+ *
  */
 static uword
 tapcli_tx (vlib_main_t * vm,
@@ -192,9 +226,9 @@ tapcli_tx (vlib_main_t * vm,
       if (writev (ti->unix_fd, tm->iovecs, vec_len (tm->iovecs)) < l)
 	clib_unix_warning ("writev");
     }
-    
+
   vlib_buffer_free(vm, vlib_frame_vector_args(frame), frame->n_vectors);
-    
+
   return n_packets;
 }
 
@@ -206,8 +240,8 @@ VLIB_REGISTER_NODE (tapcli_tx_node,static) = {
 };
 
 enum {
-  TAPCLI_RX_NEXT_IP4_INPUT, 
-  TAPCLI_RX_NEXT_IP6_INPUT, 
+  TAPCLI_RX_NEXT_IP4_INPUT,
+  TAPCLI_RX_NEXT_IP6_INPUT,
   TAPCLI_RX_NEXT_ETHERNET_INPUT,
   TAPCLI_RX_NEXT_DROP,
   TAPCLI_RX_N_NEXT,
@@ -215,6 +249,17 @@ enum {
 
 
 
+/**
+ * @brief Dispatch tapcli RX node function for node tap_cli_rx
+ *
+ *
+ * @param *vm - vlib_main_t
+ * @param *node - vlib_node_runtime_t
+ * @param *ti - tapcli_interface_t
+ *
+ * @return n_packets - uword
+ *
+ */
 static uword tapcli_rx_iface(vlib_main_t * vm,
                             vlib_node_runtime_t * node,
                             tapcli_interface_t * ti)
@@ -352,6 +397,19 @@ static uword tapcli_rx_iface(vlib_main_t * vm,
   return VLIB_FRAME_SIZE - n_left_to_next;
 }
 
+/**
+ * @brief tapcli RX node function
+ * @node tap-cli-rx
+ *
+ * Input node from the Kernel tun/tap device
+ *
+ * @param *vm - vlib_main_t
+ * @param *node - vlib_node_runtime_t
+ * @param *frame - vlib_frame_t
+ *
+ * @return n_packets - uword
+ *
+ */
 static uword
 tapcli_rx (vlib_main_t * vm,
 	   vlib_node_runtime_t * node,
@@ -384,6 +442,7 @@ tapcli_rx (vlib_main_t * vm,
   return total_count; //This might return more than 256.
 }
 
+/** TAPCLI error strings */
 static char * tapcli_rx_error_strings[] = {
 #define _(sym,string) string,
   foreach_tapcli_error
@@ -409,19 +468,27 @@ VLIB_REGISTER_NODE (tapcli_rx_node, static) = {
   },
 };
 
-/* Gets called when file descriptor is ready from epoll. */
+
+/**
+ * @brief Gets called when file descriptor is ready from epoll.
+ *
+ * @param *uf - unix_file_t
+ *
+ * @return error - clib_error_t
+ *
+ */
 static clib_error_t * tapcli_read_ready (unix_file_t * uf)
 {
   vlib_main_t * vm = vlib_get_main();
   tapcli_main_t * tm = &tapcli_main;
   uword * p;
-  
-  /* Schedule the rx node */
+
+  /** Schedule the rx node */
   vlib_node_set_interrupt_pending (vm, tapcli_rx_node.index);
 
   p = hash_get (tm->tapcli_interface_index_by_unix_fd, uf->file_descriptor);
 
-  /* Mark the specific tap interface ready-to-read */
+  /** Mark the specific tap interface ready-to-read */
   if (p)
     tm->pending_read_bitmap = clib_bitmap_set (tm->pending_read_bitmap,
                                                p[0], 1);
@@ -431,6 +498,15 @@ static clib_error_t * tapcli_read_ready (unix_file_t * uf)
   return 0;
 }
 
+/**
+ * @brief CLI function for TAPCLI configuration
+ *
+ * @param *vm - vlib_main_t
+ * @param *input - unformat_input_t
+ *
+ * @return error - clib_error_t
+ *
+ */
 static clib_error_t *
 tapcli_config (vlib_main_t * vm, unformat_input_t * input)
 {
@@ -451,18 +527,27 @@ tapcli_config (vlib_main_t * vm, unformat_input_t * input)
   if (tm->is_disabled)
     return 0;
 
-  if (geteuid()) 
+  if (geteuid())
     {
       clib_warning ("tapcli disabled: must be superuser");
       tm->is_disabled = 1;
       return 0;
-    }    
+    }
 
   tm->mtu_buffers = (tm->mtu_bytes + (buffer_size - 1)) / buffer_size;
-  
+
   return 0;
 }
 
+/**
+ * @brief Renumber TAPCLI interface
+ *
+ * @param *hi - vnet_hw_interface_t
+ * @param new_dev_instance - u32
+ *
+ * @return rc - int
+ *
+ */
 static int tap_name_renumber (vnet_hw_interface_t * hi,
                               u32 new_dev_instance)
 {
@@ -479,6 +564,14 @@ static int tap_name_renumber (vnet_hw_interface_t * hi,
 
 VLIB_CONFIG_FUNCTION (tapcli_config, "tapcli");
 
+/**
+ * @brief Free "no punt" frame
+ *
+ * @param *vm - vlib_main_t
+ * @param *node - vlib_node_runtime_t
+ * @param *frame - vlib_frame_t
+ *
+ */
 static void
 tapcli_nopunt_frame (vlib_main_t * vm,
                    vlib_node_runtime_t * node,
@@ -494,6 +587,15 @@ VNET_HW_INTERFACE_CLASS (tapcli_interface_class,static) = {
   .name = "tapcli",
 };
 
+/**
+ * @brief Formatter for TAPCLI interface name
+ *
+ * @param *s - formatter string
+ * @param *args - va_list
+ *
+ * @return *s - formatted string
+ *
+ */
 static u8 * format_tapcli_interface_name (u8 * s, va_list * args)
 {
   u32 i = va_arg (*args, u32);
@@ -510,7 +612,17 @@ static u8 * format_tapcli_interface_name (u8 * s, va_list * args)
   return s;
 }
 
-static u32 tapcli_flag_change (vnet_main_t * vnm, 
+/**
+ * @brief Modify interface flags for TAPCLI interface
+ *
+ * @param *vnm - vnet_main_t
+ * @param *hw - vnet_hw_interface_t
+ * @param flags - u32
+ *
+ * @return rc - u32
+ *
+ */
+static u32 tapcli_flag_change (vnet_main_t * vnm,
                                vnet_hw_interface_t * hw,
                                u32 flags)
 {
@@ -562,7 +674,15 @@ static u32 tapcli_flag_change (vnet_main_t * vnm,
   return 0;
 }
 
-static void tapcli_set_interface_next_node (vnet_main_t *vnm, 
+/**
+ * @brief Setting the TAP interface's next processing node
+ *
+ * @param *vnm - vnet_main_t
+ * @param hw_if_index - u32
+ * @param node_index - u32
+ *
+ */
+static void tapcli_set_interface_next_node (vnet_main_t *vnm,
                                             u32 hw_if_index,
                                             u32 node_index)
 {
@@ -571,35 +691,40 @@ static void tapcli_set_interface_next_node (vnet_main_t *vnm,
   vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
 
   ti = vec_elt_at_index (tm->tapcli_interfaces, hw->dev_instance);
-  
-  /* Shut off redirection */
+
+  /** Shut off redirection */
   if (node_index == ~0)
     {
       ti->per_interface_next_index = node_index;
       return;
     }
-  
-  ti->per_interface_next_index = 
+
+  ti->per_interface_next_index =
     vlib_node_add_next (tm->vlib_main, tapcli_rx_node.index, node_index);
 }
 
-/* 
- * Mainly exists to set link_state == admin_state
- * otherwise, e.g. ip6 neighbor discovery breaks
+/**
+ * @brief Set link_state == admin_state otherwise things like ip6 neighbor discovery breaks
+ *
+ * @param *vnm - vnet_main_t
+ * @param hw_if_index - u32
+ * @param flags - u32
+ *
+ * @return error - clib_error_t
  */
-static clib_error_t * 
+static clib_error_t *
 tapcli_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
 {
   uword is_admin_up = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) != 0;
   u32 hw_flags;
-  u32 speed_duplex = VNET_HW_INTERFACE_FLAG_FULL_DUPLEX 
+  u32 speed_duplex = VNET_HW_INTERFACE_FLAG_FULL_DUPLEX
     | VNET_HW_INTERFACE_FLAG_SPEED_1G;
-    
+
   if (is_admin_up)
     hw_flags = VNET_HW_INTERFACE_FLAG_LINK_UP | speed_duplex;
   else
     hw_flags = speed_duplex;
-  
+
   vnet_hw_interface_set_flags (vnm, hw_if_index, hw_flags);
   return 0;
 }
@@ -614,6 +739,14 @@ VNET_DEVICE_CLASS (tapcli_dev_class,static) = {
   .no_flatten_output_chains = 1,
 };
 
+/**
+ * @brief Dump TAP interfaces
+ *
+ * @param **out_tapids - tapcli_interface_details_t
+ *
+ * @return rc - int
+ *
+ */
 int vnet_tap_dump_ifs (tapcli_interface_details_t **out_tapids)
 {
   tapcli_main_t * tm = &tapcli_main;
@@ -635,7 +768,12 @@ int vnet_tap_dump_ifs (tapcli_interface_details_t **out_tapids)
   return 0;
 }
 
-/* get tap interface from inactive interfaces or create new */
+/**
+ * @brief Get tap interface from inactive interfaces or create new
+ *
+ * @return interface - tapcli_interface_t
+ *
+ */
 static tapcli_interface_t *tapcli_get_new_tapif()
 {
   tapcli_main_t * tm = &tapcli_main;
@@ -661,6 +799,17 @@ static tapcli_interface_t *tapcli_get_new_tapif()
   return ti;
 }
 
+/**
+ * @brief Connect a TAP interface
+ *
+ * @param *vm - vlib_main_t
+ * @param *intfc_name - u8
+ * @param *hwaddr_arg - u8
+ * @param *sw_if_index - u32
+ *
+ * @return rc - int
+ *
+ */
 int vnet_tap_connect (vlib_main_t * vm, u8 * intfc_name, u8 *hwaddr_arg,
                       u32 * sw_if_indexp)
 {
@@ -683,7 +832,7 @@ int vnet_tap_connect (vlib_main_t * vm, u8 * intfc_name, u8 *hwaddr_arg,
 
   if ((dev_net_tun_fd = open ("/dev/net/tun", O_RDWR)) < 0)
     return VNET_API_ERROR_SYSCALL_ERROR_1;
-  
+
   memset (&ifr, 0, sizeof (ifr));
   strncpy(ifr.ifr_name, (char *) intfc_name, sizeof (ifr.ifr_name)-1);
   ifr.ifr_flags = flags;
@@ -829,6 +978,19 @@ int vnet_tap_connect (vlib_main_t * vm, u8 * intfc_name, u8 *hwaddr_arg,
   return rv;
 }
 
+/**
+ * @brief Renumber a TAP interface
+ *
+ * @param *vm - vlib_main_t
+ * @param *intfc_name - u8
+ * @param *hwaddr_arg - u8
+ * @param *sw_if_indexp - u32
+ * @param renumber - u8
+ * @param custom_dev_instance - u32
+ *
+ * @return rc - int
+ *
+ */
 int vnet_tap_connect_renumber (vlib_main_t * vm, u8 * intfc_name,
                                u8 *hwaddr_arg, u32 * sw_if_indexp,
                                u8 renumber, u32 custom_dev_instance)
@@ -841,6 +1003,14 @@ int vnet_tap_connect_renumber (vlib_main_t * vm, u8 * intfc_name,
     return rv;
 }
 
+/**
+ * @brief Disconnect TAP CLI interface
+ *
+ * @param *ti - tapcli_interface_t
+ *
+ * @return rc - int
+ *
+ */
 static int tapcli_tap_disconnect (tapcli_interface_t *ti)
 {
   int rv = 0;
@@ -866,6 +1036,15 @@ static int tapcli_tap_disconnect (tapcli_interface_t *ti)
   return rv;
 }
 
+/**
+ * @brief Delete TAP interface
+ *
+ * @param *vm - vlib_main_t
+ * @param sw_if_index - u32
+ *
+ * @return rc - int
+ *
+ */
 int vnet_tap_delete(vlib_main_t *vm, u32 sw_if_index)
 {
   int rv = 0;
@@ -895,6 +1074,16 @@ int vnet_tap_delete(vlib_main_t *vm, u32 sw_if_index)
   return rv;
 }
 
+/**
+ * @brief CLI function to delete TAP interface
+ *
+ * @param *vm - vlib_main_t
+ * @param *input - unformat_input_t
+ * @param *cmd - vlib_cli_command_t
+ *
+ * @return error - clib_error_t
+ *
+ */
 static clib_error_t *
 tap_delete_command_fn (vlib_main_t * vm,
 		 unformat_input_t * input,
@@ -933,7 +1122,20 @@ VLIB_CLI_COMMAND (tap_delete_command, static) = {
     .function = tap_delete_command_fn,
 };
 
-/* modifies tap interface - can result in new interface being created */
+/**
+ * @brief Modifies tap interface - can result in new interface being created
+ *
+ * @param *vm - vlib_main_t
+ * @param orig_sw_if_index - u32
+ * @param *intfc_name - u8
+ * @param *hwaddr_arg - u8
+ * @param *sw_if_indexp - u32
+ * @param renumber - u8
+ * @param custom_dev_instance - u32
+ *
+ * @return rc - int
+ *
+ */
 int vnet_tap_modify (vlib_main_t * vm, u32 orig_sw_if_index,
                      u8 * intfc_name, u8 *hwaddr_arg, 
                      u32 * sw_if_indexp,
@@ -950,6 +1152,16 @@ int vnet_tap_modify (vlib_main_t * vm, u32 orig_sw_if_index,
     return rv;
 }
 
+/**
+ * @brief CLI function to modify TAP interface
+ *
+ * @param *vm - vlib_main_t
+ * @param *input - unformat_input_t
+ * @param *cmd - vlib_cli_command_t
+ *
+ * @return error - clib_error_t
+ *
+ */
 static clib_error_t *
 tap_modify_command_fn (vlib_main_t * vm,
 		 unformat_input_t * input,
@@ -961,7 +1173,7 @@ tap_modify_command_fn (vlib_main_t * vm,
   u32 new_sw_if_index = ~0;
   int user_hwaddr = 0;
   u8 hwaddr[6];
-    
+
   if (tm->is_disabled)
     {
       return clib_error_return (0, "device disabled...");
@@ -979,7 +1191,7 @@ tap_modify_command_fn (vlib_main_t * vm,
   else
     return clib_error_return (0, "unknown input `%U'",
                               format_unformat_error, input);
-  
+
   if (unformat(input, "hwaddr %U", unformat_ethernet_address,
                &hwaddr))
     user_hwaddr = 1;
@@ -1006,6 +1218,16 @@ VLIB_CLI_COMMAND (tap_modify_command, static) = {
     .function = tap_modify_command_fn,
 };
 
+/**
+ * @brief CLI function to connect TAP interface
+ *
+ * @param *vm - vlib_main_t
+ * @param *input - unformat_input_t
+ * @param *cmd - vlib_cli_command_t
+ *
+ * @return error - clib_error_t
+ *
+ */
 static clib_error_t *
 tap_connect_command_fn (vlib_main_t * vm,
 		 unformat_input_t * input,
@@ -1095,6 +1317,14 @@ VLIB_CLI_COMMAND (tap_connect_command, static) = {
     .function = tap_connect_command_fn,
 };
 
+/**
+ * @brief TAPCLI main init
+ *
+ * @param *vm - vlib_main_t
+ *
+ * @return error - clib_error_t
+ *
+ */
 clib_error_t *
 tapcli_init (vlib_main_t * vm)
 {
diff --git a/vnet/vnet/unix/tapcli.h b/vnet/vnet/unix/tapcli.h
index e9228d7cb0e..fcd82dbf25d 100644
--- a/vnet/vnet/unix/tapcli.h
+++ b/vnet/vnet/unix/tapcli.h
@@ -14,11 +14,16 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+/**
+ * @file
+ * @brief TAPCLI definitions
+ */
 
 #ifndef __included_tapcli_h__
 #define __included_tapcli_h__
 
-#define foreach_tapcli_error                            \
+/** TAP CLI errors */
+#define foreach_tapcli_error				\
   /* Must be first. */                                  \
  _(NONE, "no error")                                    \
  _(READ, "read error")                                  \
@@ -32,6 +37,7 @@ typedef enum {
    TAPCLI_N_ERROR,
  } tapcli_error_t;
 
+/** TAP CLI interface details struct */
 typedef struct {
   u32 sw_if_index;
   u8 dev_name[64];
diff --git a/vnet/vnet/unix/tuntap.c b/vnet/vnet/unix/tuntap.c
index 967c0aca4ac..aefefc36d1a 100644
--- a/vnet/vnet/unix/tuntap.c
+++ b/vnet/vnet/unix/tuntap.c
@@ -16,12 +16,25 @@
  * limitations under the License.
  *------------------------------------------------------------------
  */
+/**
+ * @file
+ * @brief  TunTap Kernel stack (reverse) punt/inject path.
+ *
+ * This driver runs in one of two distinct modes:
+ * - "punt/inject" mode, where we send pkts not otherwise processed
+ * by the forwarding to the Linux kernel stack, and
+ *
+ * - "normal interface" mode, where we treat the Linux kernel stack
+ * as a peer.
+ *
+ * By default, we select punt/inject mode.
+ */
 
 #include <fcntl.h>		/* for open */
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
-#include <sys/types.h> 
+#include <sys/types.h>
 #include <sys/uio.h>		/* for iovec */
 #include <netinet/in.h>
 
@@ -49,58 +62,52 @@ static void tuntap_nopunt_frame (vlib_main_t * vm,
                                  vlib_node_runtime_t * node,
                                  vlib_frame_t * frame);
 
-/* 
- * This driver runs in one of two distinct modes:
- * "punt/inject" mode, where we send pkts not otherwise processed
- * by the forwarding to the Linux kernel stack, and
- * "normal interface" mode, where we treat the Linux kernel stack
- * as a peer.
- *
- * By default, we select punt/inject mode.
- */
-
 typedef struct {
   u32 sw_if_index;
   u8 is_v6;
   u8 addr[16];
 } subif_address_t;
 
+/**
+ * @brief TUNTAP node main state
+ */
 typedef struct {
-  /* Vector of iovecs for readv/writev calls. */
+  /** Vector of iovecs for readv/writev calls. */
   struct iovec * iovecs;
 
-  /* Vector of VLIB rx buffers to use.  We allocate them in blocks
+  /** Vector of VLIB rx buffers to use.  We allocate them in blocks
      of VLIB_FRAME_SIZE (256). */
   u32 * rx_buffers;
 
-  /* File descriptors for /dev/net/tun and provisioning socket. */
+  /** File descriptors for /dev/net/tun and provisioning socket. */
   int dev_net_tun_fd, dev_tap_fd;
 
-  /* Create a "tap" [ethernet] encaps device */
+  /** Create a "tap" [ethernet] encaps device */
   int is_ether;
 
-  /* 1 if a "normal" routed intfc, 0 if a punt/inject interface */
+  /** 1 if a "normal" routed intfc, 0 if a punt/inject interface */
 
   int have_normal_interface;
 
-  /* tap device destination MAC address. Required, or Linux drops pkts */
+  /** tap device destination MAC address. Required, or Linux drops pkts */
   u8 ether_dst_mac[6];
 
-  /* Interface MTU in bytes and # of default sized buffers. */
+  /** Interface MTU in bytes and # of default sized buffers. */
   u32 mtu_bytes, mtu_buffers;
 
-  /* Linux interface name for tun device. */
+  /** Linux interface name for tun device. */
   char * tun_name;
 
-  /* Pool of subinterface addresses */
+  /** Pool of subinterface addresses */
   subif_address_t *subifs;
 
-  /* Hash for subif addresses */
+  /** Hash for subif addresses */
   mhash_t subif_mhash;
 
+  /** Unix file index */
   u32 unix_file_index;
 
-  /* For the "normal" interface, if configured */
+  /** For the "normal" interface, if configured */
   u32 hw_if_index, sw_if_index;
 
 } tuntap_main_t;
@@ -108,15 +115,23 @@ typedef struct {
 static tuntap_main_t tuntap_main = {
   .tun_name = "vnet",
 
-  /* Suitable defaults for an Ethernet-like tun/tap device */
+  /** Suitable defaults for an Ethernet-like tun/tap device */
   .mtu_bytes = 4096 + 256,
 };
 
-/*
- * tuntap_tx
- * Output node, writes the buffers comprising the incoming frame 
+/**
+ * @brief tuntap_tx
+ * @node tuntap-tx
+ *
+ * Output node, writes the buffers comprising the incoming frame
  * to the tun/tap device, aka hands them to the Linux kernel stack.
- * 
+ *
+ * @param *vm - vlib_main_t
+ * @param *node - vlib_node_runtime_t
+ * @param *frame - vlib_frame_t
+ *
+ * @return rc - uword
+ *
  */
 static uword
 tuntap_tx (vlib_main_t * vm,
@@ -146,7 +161,7 @@ tuntap_tx (vlib_main_t * vm,
       if (tm->iovecs)
 	_vec_len (tm->iovecs) = 0;
 
-      /* VLIB buffer chain -> Unix iovec(s). */
+      /** VLIB buffer chain -> Unix iovec(s). */
       vec_add2 (tm->iovecs, iov, 1);
       iov->iov_base = b->data + b->current_data;
       iov->iov_len = l = b->current_length;
@@ -167,13 +182,13 @@ tuntap_tx (vlib_main_t * vm,
       if (writev (tm->dev_net_tun_fd, tm->iovecs, vec_len (tm->iovecs)) < l)
 	clib_unix_warning ("writev");
     }
-    
-  /* The normal interface path flattens the buffer chain */
+
+  /** The normal interface path flattens the buffer chain */
   if (tm->have_normal_interface)
     vlib_buffer_free_no_next (vm, buffers, n_packets);
   else
     vlib_buffer_free (vm, buffers, n_packets);
-    
+
   return n_packets;
 }
 
@@ -185,13 +200,24 @@ VLIB_REGISTER_NODE (tuntap_tx_node,static) = {
 };
 
 enum {
-  TUNTAP_RX_NEXT_IP4_INPUT, 
-  TUNTAP_RX_NEXT_IP6_INPUT, 
+  TUNTAP_RX_NEXT_IP4_INPUT,
+  TUNTAP_RX_NEXT_IP6_INPUT,
   TUNTAP_RX_NEXT_ETHERNET_INPUT,
   TUNTAP_RX_NEXT_DROP,
   TUNTAP_RX_N_NEXT,
 };
 
+/**
+ * @brief TUNTAP receive node
+ * @node tuntap-rx
+ *
+ * @param *vm - vlib_main_t
+ * @param *node - vlib_node_runtime_t
+ * @param *frame - vlib_frame_t
+ *
+ * @return rc - uword
+ *
+ */
 static uword
 tuntap_rx (vlib_main_t * vm,
 	   vlib_node_runtime_t * node,
@@ -208,7 +234,7 @@ tuntap_rx (vlib_main_t * vm,
   u32 free_list_index = dm->vlib_buffer_free_list_index;
 #endif
 
-  /* Make sure we have some RX buffers. */
+  /** Make sure we have some RX buffers. */
   {
     uword n_left = vec_len (tm->rx_buffers);
     uword n_alloc;
@@ -225,14 +251,14 @@ tuntap_rx (vlib_main_t * vm,
       }
   }
 
-  /* Allocate RX buffers from end of rx_buffers.
+  /** Allocate RX buffers from end of rx_buffers.
      Turn them into iovecs to pass to readv. */
   {
     uword i_rx = vec_len (tm->rx_buffers) - 1;
     vlib_buffer_t * b;
     word i, n_bytes_left, n_bytes_in_packet;
 
-    /* We should have enough buffers left for an MTU sized packet. */
+    /** We should have enough buffers left for an MTU sized packet. */
     ASSERT (vec_len (tm->rx_buffers) >= tm->mtu_buffers);
 
     vec_validate (tm->iovecs, tm->mtu_buffers - 1);
@@ -290,14 +316,14 @@ tuntap_rx (vlib_main_t * vm,
 #endif
       }
 
-    /* Interface counters for tuntap interface. */
-    vlib_increment_combined_counter 
+    /** Interface counters for tuntap interface. */
+    vlib_increment_combined_counter
         (vnet_main.interface_main.combined_sw_if_counters
          + VNET_INTERFACE_COUNTER_RX,
          os_get_cpu_number(),
          tm->sw_if_index,
          1, n_bytes_in_packet);
-    
+
     _vec_len (tm->rx_buffers) = i_rx;
   }
 
@@ -361,6 +387,9 @@ tuntap_rx (vlib_main_t * vm,
   return 1;
 }
 
+/**
+ * @brief TUNTAP_RX error strings
+ */
 static char * tuntap_rx_error_strings[] = {
   "unknown packet type",
 };
@@ -383,7 +412,13 @@ VLIB_REGISTER_NODE (tuntap_rx_node,static) = {
   },
 };
 
-/* Gets called when file descriptor is ready from epoll. */
+/**
+ * @brief Gets called when file descriptor is ready from epoll.
+ *
+ * @param *uf - unix_file_t
+ *
+ * @return error - clib_error_t
+ */
 static clib_error_t * tuntap_read_ready (unix_file_t * uf)
 {
   vlib_main_t * vm = vlib_get_main();
@@ -391,11 +426,14 @@ static clib_error_t * tuntap_read_ready (unix_file_t * uf)
   return 0;
 }
 
-/*
- * tuntap_exit
- * Clean up the tun/tap device
+/**
+ * @brief Clean up the tun/tap device
+ *
+ * @param *vm - vlib_main_t
+ *
+ * @return error - clib_error_t
+ *
  */
-
 static clib_error_t *
 tuntap_exit (vlib_main_t * vm)
 {
@@ -437,6 +475,15 @@ tuntap_exit (vlib_main_t * vm)
 
 VLIB_MAIN_LOOP_EXIT_FUNCTION (tuntap_exit);
 
+/**
+ * @brief CLI function for tun/tap config
+ *
+ * @param *vm - vlib_main_t
+ * @param *input - unformat_input_t
+ *
+ * @return error - clib_error_t
+ *
+ */
 static clib_error_t *
 tuntap_config (vlib_main_t * vm, unformat_input_t * input)
 {
@@ -645,6 +692,16 @@ tuntap_config (vlib_main_t * vm, unformat_input_t * input)
 
 VLIB_CONFIG_FUNCTION (tuntap_config, "tuntap");
 
+/**
+ * @brief Add or Del IP4 address to tun/tap interface
+ *
+ * @param *im - ip4_main_t
+ * @param opaque - uword
+ * @param sw_if_index - u32
+ * @param *address - ip4_address_t
+ * @param is_delete - u32
+ *
+ */
 void
 tuntap_ip4_add_del_interface_address (ip4_main_t * im,
 				      uword opaque,
@@ -659,15 +716,15 @@ tuntap_ip4_add_del_interface_address (ip4_main_t * im,
   subif_address_t subif_addr, * ap;
   uword * p;
 
-  /* Tuntap disabled, or using a "normal" interface. */
+  /** Tuntap disabled, or using a "normal" interface. */
   if (tm->have_normal_interface ||  tm->dev_tap_fd < 0)
     return;
 
-  /* See if we already know about this subif */
+  /** See if we already know about this subif */
   memset (&subif_addr, 0, sizeof (subif_addr));
   subif_addr.sw_if_index = sw_if_index;
   clib_memcpy (&subif_addr.addr, address, sizeof (*address));
-  
+
   p = mhash_get (&tm->subif_mhash, &subif_addr);
 
   if (p)
@@ -719,21 +776,31 @@ tuntap_ip4_add_del_interface_address (ip4_main_t * im,
     clib_unix_warning ("ioctl SIOCSIFFLAGS");
 }
 
-/*
- * $$$$ gross workaround for a known #include bug 
+/**
+ * @brief workaround for a known #include bug
  * #include <linux/ipv6.h> causes multiple definitions if
  * netinet/in.h is also included.
  */
 struct in6_ifreq {
 	struct in6_addr	ifr6_addr;
         u32		ifr6_prefixlen;
-	int		ifr6_ifindex; 
+        int		ifr6_ifindex;
 };
 
-/* 
+/**
+ * @brief Add or Del tun/tap interface address
+ *
  * Both the v6 interface address API and the way ifconfig
  * displays subinterfaces differ from their v4 couterparts.
  * The code given here seems to work but YMMV.
+ *
+ * @param *im - ip6_main_t
+ * @param opaque - uword
+ * @param sw_if_index - u32
+ * @param *address - ip6_address_t
+ * @param address_length - u32
+ * @param if_address_index - u32
+ * @param is_delete - u32
  */
 void
 tuntap_ip6_add_del_interface_address (ip6_main_t * im,
@@ -759,7 +826,7 @@ tuntap_ip6_add_del_interface_address (ip6_main_t * im,
   subif_addr.sw_if_index = sw_if_index;
   subif_addr.is_v6 = 1;
   clib_memcpy (&subif_addr.addr, address, sizeof (*address));
-  
+
   p = mhash_get (&tm->subif_mhash, &subif_addr);
 
   if (p)
@@ -820,6 +887,14 @@ tuntap_ip6_add_del_interface_address (ip6_main_t * im,
     }
 }
 
+/**
+ * @brief TX the tun/tap frame
+ *
+ * @param *vm - vlib_main_t
+ * @param *node - vlib_node_runtime_t
+ * @param *frame - vlib_frame_t
+ *
+ */
 static void
 tuntap_punt_frame (vlib_main_t * vm,
                    vlib_node_runtime_t * node,
@@ -829,6 +904,14 @@ tuntap_punt_frame (vlib_main_t * vm,
   vlib_frame_free (vm, node, frame);
 }
 
+/**
+ * @brief Free the tun/tap frame
+ *
+ * @param *vm - vlib_main_t
+ * @param *node - vlib_node_runtime_t
+ * @param *frame - vlib_frame_t
+ *
+ */
 static void
 tuntap_nopunt_frame (vlib_main_t * vm,
                    vlib_node_runtime_t * node,
@@ -844,6 +927,15 @@ VNET_HW_INTERFACE_CLASS (tuntap_interface_class,static) = {
   .name = "tuntap",
 };
 
+/**
+ * @brief Format tun/tap interface name
+ *
+ * @param *s - u8 - formatter string
+ * @param *args - va_list
+ *
+ * @return *s - u8 - formatted string
+ *
+ */
 static u8 * format_tuntap_interface_name (u8 * s, va_list * args)
 {
   u32 i = va_arg (*args, u32);
@@ -852,6 +944,16 @@ static u8 * format_tuntap_interface_name (u8 * s, va_list * args)
   return s;
 }
 
+/**
+ * @brief TX packet out tun/tap
+ *
+ * @param *vm - vlib_main_t
+ * @param *node - vlib_node_runtime_t
+ * @param *frame - vlib_frame_t
+ *
+ * @return n_buffers - uword - Packets transmitted
+ *
+ */
 static uword
 tuntap_intfc_tx (vlib_main_t * vm,
 		 vlib_node_runtime_t * node,
@@ -875,6 +977,14 @@ VNET_DEVICE_CLASS (tuntap_dev_class,static) = {
   .format_device_name = format_tuntap_interface_name,
 };
 
+/**
+ * @brief tun/tap node init
+ *
+ * @param *vm - vlib_main_t
+ *
+ * @return error - clib_error_t
+ *
+ */
 static clib_error_t *
 tuntap_init (vlib_main_t * vm)
 {
diff --git a/vnet/vnet/unix/tuntap.h b/vnet/vnet/unix/tuntap.h
index ba0b77938e8..d7f96caeaf0 100644
--- a/vnet/vnet/unix/tuntap.h
+++ b/vnet/vnet/unix/tuntap.h
@@ -1,4 +1,4 @@
-/* 
+/*
  *------------------------------------------------------------------
  * tuntap.h - kernel stack (reverse) punt/inject path
  *
@@ -16,10 +16,9 @@
  * limitations under the License.
  *------------------------------------------------------------------
  */
-
-/*
- * Call from some VLIB_INIT_FUNCTION to set the Linux kernel
- * inject node name.
+/**
+ * @file
+ * @brief Call from VLIB_INIT_FUNCTION to set the Linux kernel inject node name.
  */
 void register_tuntap_inject_node_name (char *name);